Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!munnari.oz.au!bruce!monu1!monu6!minyos!mg@godzilla.cgl.rmit.oz.au
From: mg@ (Mike Gigante)
Newsgroups: comp.sys.sgi
Subject: Re: Slooow backups with BRU
Message-ID: <mg.659642378@godzilla>
Date: 26 Nov 90 17:59:38 GMT
References: <1022@babcock.cerc.wvu.wvnet.edu>
Sender: news@minyos.xx.rmit.oz.au
Lines: 15

I don't know about 1/2" tapes, but on our exabyte, we sped bru up
*considerably* by increasing the buffer size to ~ 1Mb. Unfortunately
I have found the double-buffering option to bru to be unreliable as
this would be even faster.

e.g. bru -cv -b 1Mb -f /dev/xtape ...

the larger buffer reduces all the back and forth tape motion that
is needed to get to streaming speed (for a little 20k write).

buffers larger than 1Mb didn't seem to win much. (This was a very
qualitative trial!!)

Mike Gigante,
RMIT Australia